Video conferencing systems that allow two-way video communication between two or more users or conferees at different sites in real-time are known. Typically, each conferee's site is equipped with a video camera and a display. The video camera and display are coupled to a communications network. In this manner, video signals captured by the video camera can be transmitted over the communications network to one or more displays at remote sites and video signals received from the communication network that were transmitted by one or more video cameras at a remote sites can be displayed. Typically, a microphone and a speaker are also present at each site to record and playback corresponding audio signals respectively, in a generally synchronized manner.
One of the most commonly encountered problems with video conferencing systems is the “off camera” problem, also referred to as the “parallax effect”, whereby conferees appear as being unable to establish direct eye contact while looking at their respective displays. Ideally, the video camera is placed in a space directly in front of each conferee. Unfortunately however, the display also occupies space in front of each user. As a result, the video camera is placed away from its ideal location, typically just above, just below, or just to the side of the display. If the video camera is not placed directly in front of the user, the user will appear to be looking off to the side, above or below the line of sight that corresponds to direct eye contact, depending on the placement of the video camera. This “off camera” or “parallax effect” is undesirable.
An exemplary conventional video conferencing system 10 is shown in FIG. 1. As can be seen, at a local site an imaging device such as video camera 22-1 connected to a computer 24-1 is placed above a display 26-1 for use by a first conferee U1. Similarly, at a remote site, an imaging device such as video camera 22-2 connected to computer 24-2 is placed above a remote display 26-2 for use by a second conferee U2. The two computers 24-1 and 24-2 communicate via a communications network 28 such as for example a local area network (LAN) or a wide area network (WAN) such as for example the Internet.
Displays 26-1 and 26-2 are standard liquid crystal display (LCD) or cathode ray tube (CRT) monitors. Video cameras 22-1 and 22-2 can be stand-alone cameras or embedded web-cams that are formed integrally with displays 26-1 and 26-2 respectively. Each computer 24-1 and 24-2 processes captured images from its respective video camera 22-1 and 22-2 for transmission.
As noted above, video conferencing system 20 depicted in FIG. 1 suffers from the ‘off camera’ problem or ‘the parallax effect’ problem. The conference users U1 and U2 would appear unable to establish direct eye contact while looking at their respective displays 26-1 and 26-2.
Known approaches to counteract this effect have sometimes involved placing beam-splitters or partial mirrors between the display and the conferee so that the camera records a reflected image of the conferee while the conferee is simultaneously looking directly at a display. One such approach is described in International PCT Application Publication No. WO 2007/087142 to Hunter et al.
Other approaches utilize a wide-angle lens camera, a homing device placed on a conferee and corresponding sensors, and use image manipulation techniques to provide the appearance of eye contact. One such technique is described in U.S. Pat. No. 5,438,357 to McNelley.
Unfortunately, the above described approaches often entail costs associated with additional hardware such as beam splitters or mirrors, wide-angle lens cameras, homing devices, and the associated costs. Accordingly, it is the object to provide a novel video conferencing display device.